1. Field of the Invention
The present invention discloses using changes in a magnetic field to perform sophisticated command control and data input into a portable device and, more particularly, using magnetic sensors in hand-held devices to detect changes in a magnetic field that accompany deliberate motion or movement of the devices.
2. Summary of the Related Art
Portable devices and especially, although not exclusively, portable wireless devices, e.g., mobile phones, cordless phones, text messaging device, pagers, talk radios, portable navigation systems, portable music players, portable video players, portable multimedia devices, personal digital assistants (PDAs), portable games, and the like, are used in everyday day life. Conventionally, user command input and data input into portable devices have been performed using an input device such as a keyboard entry, button pressing or handwriting using a stylus or digital pen. As portable devices become more sophisticated, traditional button or handwriting entry may be insufficient to command or input information into the device efficiently or, disadvantageously, the data are too cumbersome to do so quickly.
The development of motion sensors, e.g., motion sensing accelerometers, moving the portable device itself can be used to command the portable device and/or input data as easily as inputting information into the device conventionally. For example, U.S. Pat. No. 5,864,635 to Zetts, et al. discloses methods and systems for detecting a set of strokes input by a stylus and categorizing the strokes as either a gesture or handwriting. U.S. Pat. No. 5,583,543 to Takahashi, et al. discloses a processing device with a gesture command judging section. The gesture command judging section recognizes a gesture command using trace coordinates of a line drawing. Data are input using the positional relationship between a pen and a screen. U.S. Pat. No. 6,249,606 to Kiraly, et al. discloses methods and systems for gesture recognition in which a cursor directing device, e.g., a mouse, is used to track and record gestures.
These systems, however, require an additional portable element for command control data input. Moreover, the motion sensing elements of these devices only rely on the relative movement of the stylus, pen, mouse, and the like.
Therefore, it would be desirable to provide methods, devices, and systems for command control and data input using the portable device itself. Furthermore, it would be desirable to provide methods, devices, and systems for command control and data input that use not only the motion or movement of the portable device but, that, moreover, are adapted to sense changes in at least one of the strength and the direction of a magnetic field that accompany deliberate motion or movement of the portable device, to provide the command control and data input.